Alexander aigner



No. 607,814. Patented July .26, I898. A. AIGNER.

PARALLEL MOTION FOR DRAWING BOARDS.

(Application filed Sept. 25, 1897.)

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Nrre Tarps ALEXANDER AIGNER, OF BUDA-PESTH, AUSTRIA-HUNGARY.

PARALLEL MOTION FOR DRAWING-BOARDS.

SBFCIFICATION forming part of Letters Patent No. 607,814, dated July 26,1898.

Application filed September 25,1897. Serial No. 653,060. (No model.)

To all wholn it may concern:

Be it known that I, ALEXANDER AIGNER, a subject of the King of Austria-llnngary, residing at Buda-Pesth, Austria-Hungary, have invented certainnew and useful Improvements in Parallel Motions for Drawing- Boards, ofwhich the following is a specification.

The object of this invention is to provide an appliance for the parallelguiding of rulers on drawingboards.

The appliance can be attached to any kind of drawing-boards.

The invention is designed to prevent the inaccuracies resulting from theunevenness of the drawing-board sides and the ledge of the T-square bythe application of a simple mechanism easy to handle. This result isobtained without interfering in any manner with the independent use ofthe drawingboard and without influence upon its dimensions, either inheight or width.

By means of this appliance more rapid and accurate drawing isfacilitated, and hence a saving of work and time are brought about.

In the accompanying drawings the invention is illustrated, in whichFigure 1 shows a drawing-board provided with the new appliance in a viewfrom below. Fig. 2 represents the clip or dog appliances employed. Fig.3 is a lateral View of the rollers applied in pairs at three corners ofthe drawing'board. Fig. 4 is a lateral view of the adjustable pair ofrollers attached to the fourth corner of the drawing-board. Fig. 5 is aview taken sectionally through the drawingboard. Fig. 6 shows anotherform of the clip or dog attachment for the Tsquare, and Fig. 7 showssuch appliance for the rollers. Fig. 8 shows still another modificationof the clip or dog attachments.

As shown in Fig. 1, four corner-pieces I, II, III, and IV are attachedin a permanent stationary manner to the four corners on the back of thedrawing-board R. Of these the ones designated I, II, and III are ofeven'size.

They consist, as appears from the lateral view Fig. 3, of a plate aand'two strap-pulleys Z), which roll easily. The corner-pieces I and IIIare attached lengthwise, halving the right angle, while corner-piece IIis placed broadside. Oorner -piece IV, which serves for tightening thecable and at the same time for the insertion of the ruler, consists, asshown in the lateral view Fig. 4, of an angle-plate a and the guide forthe rollers or pulleys, these being adjustable in the arms of theangle-plate by means of the ti ghtenin g-screws c. A thin supple cable Eis stretched over the eight rollers of the four corner-pieces in therotation designated by the numbers of the various rollersnamely, 1, 2,3, 4, 5, 6, 7, and 8and the two ends are spliced or joined together. Thetightening-screws c are tight ened sufficiently to allow the cable toglide easily over the rollers. The cable is guided over the rollers orpulleys in such a manner that the corresponding outer and inner cableparts on opposite sides ofthe frame move in the same direction, as shownby the arrows in Fig. 1. the ruler T in any manner desired in accordancewith the height or width of the drawingboard by the assistance of theclips or dog attachments described hereinafter.

For the protection of the tightened cable a guard-ledge F, Figs. 1 and5, is provided at the four edges of the drawing-board. Thisguarding-ledge reaches as faras the cornerpieces, leaving the latteropen, so that the cable can be renewed easily whenever such contingencybecomes necessary.

IVhile the drawin g-board must be supplied with the cable-rollers orstrap-pulleys and with the endless cable for the employment of the newapparatus, the draftsman will only require two clips or dogs, which hecan use on any drawing-board, owing to their construction. These clipsor dogs serve for thetemporary attachment of the ruler to the cable.v

The clip or dog represented in Fig. 2, A, B, and 0, consists of a jaw orholder d, adapted to receive the'ruler,which is held by means of thescrew 6 when laid on the drawing-board R. A square pin f is attached tothe holder.

This pin points downward, and a catch-piece g 011 this pin holds thecable. This catch- This makes it possible to employ.

ing screws are turned toward the draftsman, whether the 'board is usedlengthwise or broadside. The ruler is laid on the lower edge of thedrawing-board in such a manner that both ends of the same overreach thedrawing-board. Then the one clip or dog is pushed from below on theruler at the edge of the drawing-board while the cable-holder g isentirely open, and the clip is fastened to the ruler by the screws.After this the cable-holder is attached to the cable by the screw. Thesame operation is performed with the second clip or dog at the otherside of the ruler; but to allow of an easier movement a play of aboutone millimeter must be allowed between the two clips and the edges ofthe drawing-board.

Should the ruler be set to a line already drawn beforehand, it can beset sharply on the line by means of the cable-tightening screws,

as atightening or loosening of the same effects a displacement of theruler attached to the cable.

These clips, Figs. 6, A B O, consist only of the holder m with thetightening-screw 12 means of the lower nut r the two arms of theholding-spring are pressed together, and the cable is caughtaccordingly. Moreover, the clips can be further simplified for schooluse in that they may be bent out of one piece, Fig. 8, and adapted for anormal dimension of drawing-board and ruler. In Fig. 8, d shows anelastic vise or holder, e the screw for fastening the ruler, and f anoblique angle, on the lower arm g of which a little plate 72/ and ascrew 7; are adapted to hold the cable between the side g and the plateIt. The cable-rollers for this apparatus, as shown in Fig. 7, arestamped out of two round'sheet plates Z, which are connected by claspsu, stamped out at the same time. The clip shown in Fig. 8 consists ofthe holder d", into which the tightening-screws e, intended for thefastening of the ruler, are screwed from above.

I claim In combination in a drawing-board of rectangular form, a pair ofpulleys arranged at each corner of the board, two of said pairs beingarranged with their axes on the hypotenuse of the right angle at thecorner while the pulleys of the other two pairs have their axes on linesdividing the right angles, the cable extending around said pulleys andhaving its outer portions running in the same direction while its innerportions run in the opposite direction, the ruler and the clamps forattaching the same to the cable and the means for adjusting the cable,substantially as described.

I11 witness whereof I have hereunto set my hand in presence of twowitnesses.

ALEXANDER AIGNER. v

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